Apparatus for feeding a flattened tube of flexible material



Nov. 30, 1965 M. NUSSBAUM 3,220,627

APPARATUS FOR FEEDING A FLATTENED TUBE 0F FLEXIBLE MATERIAL 2 Sheets-Sheet 1 Filed June 5, 1963 Nov. 30, 1965 M. NUSSBAUM APPARATUS FOR FEEDING A FLATTENED TUBE OF FLEXIBLE MATERIAL 2 Sheets-Sheet 2 Filed June 5, 1963 FIG. 3

FIG. 4

United States Patent 3,220,627 APPARATUS FOR FEEDING A FLATTENED TUBE OF FLEXIBLE MATERIAL Manfred Nussbaum, Plochingen, Wurttemberg, Germany,

assignor to Fr. He'sse'r Maschinenfabrik-Aktiengesellschaft, Stuttgart-Bad Cannstatt, Germany, a corporation of Germany Filed June 5, 1963, Ser. No. 285,702 Claims priority, application Germany, July 17, 1962,

I H 46,406 2 Claims. (Cl. 226-173) This invention relates to an apparatus for feeding a flattened tubular web or tube of flexible material which is guided over a feed drum in a loop of predetermined angular span.

It is known to feed continuous Webs of paper, cardboard or the like by means of drums or pairs of draw rollers. In the former case, the web is carried around the rotary drum in a loop of a predetermined angular span, a feed movement being transmitted to the web by the rotation of the drum and through the friction between the periphery of the latter and the web. In the case of pairs of draw rollers the web is conveyed between the two rollers which are pressed together and one at least of which is driven.

It has been found that these known devices for feeding flattened tubular webs or tube may sometimes be unsuitable, particularly in the case of thin plastic sheet material. Uncontrollable slipping may occur in the case of drum feed and, in feeding by means of a pair of draw rollers, the two opposed walls of the web or of the tubing may shift relatively to one another. This phenomenon is found to be particularly marked in the case of tubing with side gussets.

It is an object of the present invention to overcome these disadvantages.

In accordance with the present invention this is achieved with the apparatus referred to above by associating with the feed drum a plurality of clamping jaws which turn in unison therewith and are mounted for movement relatively to the periphery of the drum, these movements being so controlled that the jaws are pressed against the periphery of the drum only during the passage of the web or tube through the zone of the loop and thereby to hold the fed web or tube firmly against the drum at this time.

This apparatus will ensure that the web or tube is forwarded in accurate register with the periphery of the drum at a rate corresponding to that of rotation of the latter, i.e. without relative shift or buckling up.

A preferred embodiment of the invention is illustrated by way of example in the accompanying diagrammatic drawings, in which:

FIGURE 1 is a diagrammatic illustration of the apparatus, in cross-section taken along the line I-I in FIGURE 2,

FIGURE 2 is a cross-section on the line IIII of FIGURE 1,

FIGURE 3 is an enlarged side view of one of the gripper devices, with parts in section, and

FIGURE 4 is a plan view of the device in FIGURE 3.

The example illustrated in the drawings is a device for feeding a flattened tubular web or tube 1 to a bag making machine or the like (not shown). The tube 1 is conducted from a supply reel 2 over two guide rollers 3 and 4 to a feed drum, and from there over a further guide roller 6 in such manner as to form in the tube 1 a loop with an angular span of more than 180, around the feed drum 5. Thereafter the flattened tube, which is forwarded intermittently or continuously, runs over a roller 7, a jockey roller 8, and a further roller 9 to an operating mechanism (not shown) of the machine being supplied 3,220,627 Patented Nov. 30, 1965 ice with the tube material. The feed drum 5 turns at a speed related to the working rate of this mechanism.

To ensure a slip-free feed, two pairs of clamping jaws 15 are arranged on the feed drum 5 for rotation there with and serve to clamp the tube 1 against the periphery of the drum in the zone of the loop. Each of the clamping jaws 15 is carried by a bellcrank lever 16 which is pivotally mounted between bearing lugs 49 on the drum 5, so as to be pivotable in a plane transverse to the direction of feed of the tube. The clam-ping jaws 15 are arranged to be operated in such manner that they swing against the feed drum 5 at the beginning of the zone of the loop in the tube so as to apply the tube firmly against the periphery of the drum, and that they pivot away again shortly before the end of the loop zone to release the tube. For this purpose a fixed edge cam 17 is arranged at each side of drum 5 on the fixed axle 18 of the latter, and rollers 19 are mounted on the end of each bellcrank lever 16 and run on the corresponding cam 17. A lever 20 secured to the spindle of each lever 16 retains the corresponding roller 19 in constant contact with the periphery of its cam 17 by means of the tension spring 21 which is connected to opposed upper and lower rollers 19 at each side of the drum.

Each clam-ping jaw 15 is provided with a rubber lining 40 and to ensure that this makes uniform contact with the drum 5 and the tube 1, each of these jaws 15 is mounted for pivoting to a limited degree transversely to the direction of rotation of the feed drum on a pin 41 secured to the associated bellcrank lever 16. Each pin 41 carries a horizontal bearing pin 50 which accommodates the corresponding clamping jaw 15. The pins 41 are adjustable on the levers 16, by means of nuts 42, 43 to enable the position of the corresponding clamping jaws 15 to be adjusted in relation to the feed drum 5.

To increase the resistance to slip, the peripheral surface of the feed drum 5 is also provided with a rubber layer 22.

The feed drum 5 has two side-by-side driving pinions 25, 26 coupled respectively by chains 27, 28 to chain wheels 29, 30. Either of the chain wheels 29, 30, which are of different tooth pitch, can be coupled by the related magnetic clutch 31 or 32 to a continuously driven shaft 33. Normally the clutch 32 of the smaller chain wheel 30 is engaged, but if the feed loop formed between the rollers 7 and 9 by the jockey roller 8 is taken up excessively, that is to say becomes too short, the other clutch 31, of the larger chain wheel, is automatically brought into effect for a short period to speed up the drum, at the same time disengaging the clutch 32. I

To implement this, the pivotable arm 35 carrying jockey roller 8 is arranged to engage a fixed switch contact 36 which, through a connection 47, controls a relay 45 and, through this, the brushes 46 and slip rings 48 connecting clutches 31 and 32 to their electrical supply.

It is to be understood that, where it is only required to feed narrow webs or tubes, the clamping jaws 15 need be provided at one side only of the drum '5. Furthermore the drum 5 can be provided with more than two clamping jaws 15 or pairs of clamping jaws arranged at uniform distances from one another, thereby providing the facility to make the angular range of the loop smaller, but nevertheless to ensure that at all times at least one clamping jaw 15 or a pair of such clamping jaws presses the tube or web 1 against the periphery of the drum.

Iclaim:

1. Apparatus for feeding a flattened tube of flexible material, comprising a feed drum, a drive source, plural transmission means for rotating the drum from said drive source, clutch means for selective engagement of one or other of said transmission means, detector means in the path of travel of the tube from the drum for controlling 3 said clutch means, at least one tube clamping jaw mounted on, and movable relatively to, said drum and means for moving said jaw relatively to the drum, in response to rotation of the latter, to engage the jaw against the drum during a predetermined portion only of the rotation thereof.

2. Apparatus for feeding a flattened tube of flexible material, comprising a feed drum, a driving shaft, first and second toothed transmission means for rotating said drum from said shaft, first and second magnetic clutches respectively engaging said first and second toothed transmission means with said driving shaft, an electrical system controlling said magnetic clutches and incorporating an operating switch, a jockey roller bearing against the tube leaving said drum and cooperating with said switch,

References Cited by the Examiner UNITED STATES PATENTS 635,090 10/ 1899 Claussen et al 9322 938,174 10/1909 Shaw 226190 X 1,472,902 11/1923 Bulkeley 226-173 X M. HENSON WOOD, JR., Primary Examiner.

RAPHAEL M. LUPO, ROBERT B. REEVES, Examiners. 

1. APPARATUS FOR FEEDING A FLATTENED TUBE OF FLEXIBLE MATERIAL, COMPRISING A FEED DRUM, A DRIVE SOURCE, PLURAL TRANSMISSION MEANS FOR ROTATING THE DRUM FROM SAID DRIVE SOURCE, CLUTCH MEANS FOR SELECTIVE ENGAGEMENT OF ONE OR OTHER OF SAID TRANSMISSION MEANS, DETECTOR MEANS IN THE PATH OF TRAVEL OF THE TUBE FROM THE DRUM FOR CONTROLLING SAID CLUTCH MEANS, AT LEAST ONE TUBE CLAMPING JAW MOUNTED ON, AND MOVABLE RELATIVELY TO, SAID DRUM AND MEANS FOR MOVING SAID JAW RELATIVELY TO THE DRUM, IN RESPONSE TO ROTATION OF THE LATTER, TO ENGAGE THE JAW AGAINST THE DRUM DURING A PREDETERMINED PORTION ONLY OF THE ROTATION THEREOF. 